Tissue fixation --- formalin

1. Place tissue specimens directly onto wet ice or into 10% neutral buffered formalin immediately after surgical removal or biopsy.

2. For sectioning, grossly process the tissue specimen into thin sections (< 3 mm) or cut into small pieces. Uncut tissues can be preserved in formalin.

3. Place into a large container with at least 10 volumes of 10% neutral buffered formalin and fix overnight.

Note: The routine fixative formalin preserves the tissue morphology, it also cross-links RNA and DNA to protein. Although not impossible, it will be less preferable for PCR or other molecular applications. Ethanol fixation or snap freezing may be used instead.